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Can someone explain how this makes any sense.
TPR FL 1 # 9 Spoiler - Electron Affinity
- Thread starter betterfuture
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Can someone explain how this makes any sense.
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This is a poorly worded answer, and I understand why it doesn't make sense. I think they simply wrote it wrong.
We know that electron affinity decreases as we go down the periodic table.
Chlorine has a larger atomic volume than fluorine, its bonding electrons are further away from the nucleus, are better shielded from the nuclear charge and so are not as attracted to the nucleus. This makes it less electronegative than fluorine.
I may just be unfamiliar with how increased electron repulsion can increase electronegativity, but I think TPR may do well to reference what I mentioned above as its question answer instead.
We know that electron affinity decreases as we go down the periodic table.
Chlorine has a larger atomic volume than fluorine, its bonding electrons are further away from the nucleus, are better shielded from the nuclear charge and so are not as attracted to the nucleus. This makes it less electronegative than fluorine.
I may just be unfamiliar with how increased electron repulsion can increase electronegativity, but I think TPR may do well to reference what I mentioned above as its question answer instead.
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Did you mean to say electron affinity here?
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Yes I should have said electron affinity to keep in line with the question.
Just as a bonus, they are very similar and track together on periodic trends.
Electron affinity is how much energy is released when an electron is gained, it is quantitative.
Electronegativity is a molecule's ability to attract an electron and form a covalent bond, it is qualitative.
But - they aren't synonymous so I shouldn't have treated them as if they were.
Just as a bonus, they are very similar and track together on periodic trends.
Electron affinity is how much energy is released when an electron is gained, it is quantitative.
Electronegativity is a molecule's ability to attract an electron and form a covalent bond, it is qualitative.
But - they aren't synonymous so I shouldn't have treated them as if they were.
TPR is just testing an exception to the electron affinity rule where fluorine actually wants an electron less than chlorine. Again, this is a nitpicky exception and not what you should focus on - that's why TPR is the worst test prep company for the MCAT, in my opinion. What they're trying to get at there is that fluorine is very small and so if you add an electron, it goes into the 2p shell and is in close proximity to the other electrons whereas with chlorine, you're adding to the 3p shell which is more dispersed and so the added electron is farther away from the other electrons. Don't worry about getting this right because you're not going to be asked something like this on the MCAT.
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I don't necessarily think this is a question to be written off.
You narrowed it down to two choices, which both say that fluorine has a smaller atomic volume. If you decrease the atomic volume, then that logically means that the electrons have to be closer to each other. Would electrons closer to each other result in weaker or stronger repulsive forces? That gives you the answer.
They might be right that the content may not be tested on or whatever, but I think its worthwhile to see how you could have reasoned the correct answer.
You narrowed it down to two choices, which both say that fluorine has a smaller atomic volume. If you decrease the atomic volume, then that logically means that the electrons have to be closer to each other. Would electrons closer to each other result in weaker or stronger repulsive forces? That gives you the answer.
They might be right that the content may not be tested on or whatever, but I think its worthwhile to see how you could have reasoned the correct answer.
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Thank you! I guess my timing is not quite down because whenever I look back at my mistakes I almost always say "I could have easily gotten that right if I had another minute or so to think." Timing really screws me over in the C/P section. Guess I have to work on that! Thank you though!
